"Despite the great medical care at numerous facilities, Bobbi Kristina Brown's condition has continued to deteriorate," Pat Houston told ET in a statement Wednesday. "As of today, she has been moved into hospice care. We thank everyone for their support and prayers. She is in God's hands now."

In hospice care, a team of caregivers -- which generally includes a mix of physicians, nurses, grief counselors, clergy and volunteers -- work together to provide end-of-life services and keep the patient comfortable as the body shuts down.

"It doesn’t hasten your death -- or prolong your death," explained Jon Radulovic, spokesperson for the National Hospice and Palliative Care Organization. "The body is following its natural path, but hospice is there to make it more comfortable." According to the organization, an estimated 1.5 million patients received hospice care in 2013.

A source close to the family told ET on Wednesday that Brown's organs were failing, and that she had stopped receiving all medications. That could include ending any sources of artificial nutrition and hydration for the 22-year-old, Radulovic said.

"You're talking about a situation where cure and rehabilitation are not possible," Radulovic said. "People think, doctors can always do something, but there are times when the damage is so severe, particularly to the brain, where that is not possible."

Radulovic described hospice care -- which could last days or even weeks, and may include pain management -- as a quiet, often peaceful process leading to a natural death. "There is not much visible activity," he said. "Her pulse rate would decline, her heart rate would decline, and her body would use less energy."

"It's a very brave choice that families make," he said. "We encourage people to complete advance directives so they can talk about what they would do if they were in that situation."

Sometimes another death in the family -- such as that of Brown's mother, Whitney Houston, who died in 2012 -- may prompt such a discussion. "After her mother, it's possible that it is something the family did talk about," he said.

When asked about end of life decisions for Bobbi Kristina, the Brown and Houston families have often discussed their deep religious convictions. In May, Brown's grandmother Cissy Houston told ET, "Whatever the Lord decides, I'm ready for her... I have nothing to do with that. That's His job. It's His territory, you know? And I understand it."

Radulovic recalled that even Pope John Paul II opted to die at home at the Vatican after having had his feeding tube removed. "All of us are mortal beings and our bodies can't run forever," he said. "Medical science can only go to a point."